index(3)                (BSD Compatibility Package)                index(3)


   NAME
         index, rindex - string operations

   SYNOPSIS
         #include <string.h>

         char *index(s, c)
         char *s, c;

         char *rindex(s, c)
         char *s, c;

   DESCRIPTION
         These functions operate on NULL-terminated strings.  They do not
         check for overflow of any receiving string.

         index and rindex returns a pointer to the first (last) occurrence of
         character c in string s, or a NULL pointer if c does not occur in the
         string.  The NULL character terminating a string is considered to be
         part of the string.

   SEE ALSO
         bstring(3), strings(3)

         malloc(3C) in the Programmer's Reference Manual.

   NOTES
         For user convenience, these functions are declared in the optional
         <strings.h> header file.

         On the Sun processor, as well as on many other machines, you can not
         use a NULL pointer to indicate a NULL string.  A NULL pointer is an
         error and results in an abort of the program.  If you wish to
         indicate a NULL string, you must have a pointer that points to an
         explicit NULL string.  On some implementations of the C language on
         some machines, a NULL pointer, if dereferenced, would yield a NULL
         string; this highly non-portable trick was used in some programs.
         Programmers using a NULL pointer to represent an empty string should
         be aware of this portability issue; even on machines where
         dereferencing a NULL pointer does not cause an abort of the program,
         it does not necessarily yield a NULL string.

         Character movement is performed differently in different
         implementations.  Thus overlapping moves may yield surprises.









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